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if $$ 2sin^{2}\theta+3sin\theta -2=0 $$ , $$ 0^\circ<\theta<90^\circ $$ then value of $$ \theta $$ is
$$2sin^{2}\theta+3sin\theta -2=0$$
$$=$$> $$2\sin^2\theta-\sin\theta\ +4\sin\theta-2=0$$
$$=$$> $$\sin\theta\ \left(2\sin\theta\ -1\right)+2\left(2\sin\theta-1\right)=0$$
$$=$$> $$\left(2\sin\theta\ -1\right)\left(\sin\theta\ +2\right)=0$$
$$=$$> $$2\sin\theta\ -1=0$$ (or) $$\sin\theta\ +2=0$$
$$=$$> $$\sin\theta\ =\frac{1}{2}$$ (or) $$\sin\theta\ =-2$$
$$\sin\theta\ =-2$$ is not possible
$$\therefore\ \sin\theta\ =\frac{1}{2}$$
$$=$$> $$\theta\ =30^{\circ\ }$$ since $$0^{\circ\ }<\theta<90^{\circ\ }\ $$
Hence, the correct answer is Option D
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